Virtual Phase Dynamics for Constrained Geometries in a Soap Froth
Soap froths as typical disordered ellular structures, exhibiting spatial and t empoal evolution, have been studied through their distributions and topological properties. Recently, persistence has been introduced as a non-topological probe to study froth dynamis at different length scales and to view the froth as a two-phase system. Using a direct simulation method, we have investigated virtual phase dynamcis in 2D artificial froths with various initial structures corresponding to controlled disorder. In particular, we examine the special case of a defect ring surrounding a central inclusion in a uniform froth, for different percentages of persistent cells, where this geometry permits comparison with shell-theory. It appears that defect location and pattern of cell inclusion in the virtual phase cause considerable variation in the evolutionary behaviour, leading to non-universal exponents for the phase dynamics. This is probably explained by the fact that the froth is still in the transient period over simulation time-scales, rather than achieving the final stage of persistence. However, distinctive patterns of response can be identified for the different froth regions, despite the limitations on system size.
Keywordspersistence defect ring phase dynamics constrained geometries transience
- 4.Ruskin, H.J., Feng, Y: Cellular networks: characterising disorder in froths Trends in Stat. Phys. 2 (1998) 131–152Google Scholar
- 5.von Neumann J.: Grain shapes and other metallurgical applications of topology Metal Interfaces 41 (1952) 108–110Google Scholar
- 17.Tarn, W.Y., Rutenberg, A.D., Szeto, K.Y., Vollmayr-Lee, B.P.: Cluster persistence: A discriminating probe of soap froth dynamics Europhys. Lett. 51 (2000) 223–229Google Scholar
- 18.Majumdar, S.N.: Persistence in nonequilibrium systems Curr. Sci. 77 (1999) 370–375Google Scholar
- 24.Feng, Y., Ruskin, H.J., Zhu, B.: 2002 (in preparation)Google Scholar